arXiv subjects

Stanislaw Kurdzialek

Publications and source records attributed to Stanislaw Kurdzialek.

8 recordsLinked to original sources

arXiv2026

Super-resolution microscopy via fluctuation-enhanced spatial mode demultiplexing

We introduce a superresolution technique that combines spatial mode demultiplexing (SPADE) with emitter blinking. We show that temporal fluctuations not only enhance the precision of SPADE imaging, but also drastically simplify the measurement required to recover full object information---in the presence of fluctuations, SPADE can be replaced by the much simpler image inversion interferometry. Both gains are enabled by exploiting temporal cumulants of the detected signal. We further show that the proposed fluctuation-enhanced techniques are significantly more robust to dark-count noise than conventional SPADE.

physics.optics↗

arXiv2025

Universal bounds for quantum metrology in the presence of correlated noise

We derive fundamental bounds for general quantum metrological models involving both temporal or spatial correlations (mathematically described by quantum combs), which may be effectively computed in the limit of a large number of probes or sensing channels involved. Although the bounds are not guaranteed to be tight in general, their tightness may be systematically increased by increasing numerical complexity of the procedure. Interestingly, this approach yields bounds tighter than the state of the art also for uncorrelated channels. We apply the bound to study the limits for the most general adaptive phase estimation models in the presence of temporally correlated dephasing. We consider dephasing both parallel (no Heisenberg scaling) and perpendicular (Heisenberg scaling possible) to the signal. In the former case our new bounds show that negative correlations are beneficial, for the latter we show evidence that the bounds are tight. We also apply the bounds to collisional thermometry, i.e. estimation of a parameter of the environment, showing evidence that entangled probes may provide only a limited advantage.

quant-ph↗

arXiv2025

Quantum metrology using quantum combs and tensor network formalism

We develop an efficient algorithm for determining optimal adaptive quantum estimation protocols with arbitrary quantum control operations between subsequent uses of a probed channel. We introduce a tensor network representation of an estimation strategy, which drastically reduces the time and memory consumption of the algorithm, and allows us to analyze metrological protocols involving up to $N=50$ qubit channel uses, whereas the state-of-the-art approaches are limited to $N<5$. The method is applied to study the performance of the optimal adaptive metrological protocols in presence of various noise types, including correlated noise.

quant-ph↗

arXiv2023

Measurement noise susceptibility in quantum estimation

Fisher Information is a key notion in the whole field of quantum metrology. It allows for a direct quantification of maximal achievable precision of estimation of parameters encoded in quantum states using the most general quantum measurement. It fails, however, to quantify the robustness of quantum estimation schemes against measurement imperfections, which are always present in any practical implementations. Here, we introduce a new concept of Fisher Information Measurement Noise Susceptibility that quantifies the potential loss of Fisher Information due to small measurement disturbance. We derive an explicit formula for the quantity, and demonstrate its usefulness in analysis of paradigmatic quantum estimation schemes, including interferometry and super-resolution optical imaging.

quant-ph↗

arXiv2023

Noise Resistant Phase Imaging with Intensity Correlation

Interferometric methods, renowned for their reliability and precision, play a vital role in phase imaging. Interferometry typically requires high coherence and stability between the measured and the reference beam. The presence of rapid phase fluctuations averages out the interferogram, erasing the spatial phase information. This difficulty can be circumvented by shortening the measurement time. However, shortening the measurement time results in smaller photon counting rates precluding its applicability to low-intensity phase imaging. We introduce and experimentally demonstrate a phase imaging technique that is immune to position-independent, time-dependent phase fluctuation. We accomplish this by measuring intensity correlation instead of intensity. Our method enables using long measurement times and is therefore advantageous when the photon flux is very low. We use a Fisher information-based approach to show that the precision of phase reconstruction achieved using our method is in fact the best achievable precision in the scenario when two photons are detected per phase stability time.

physics.optics↗

arXiv2023

Using adaptiveness and causal superpositions against noise in quantum metrology

We derive new bounds on achievable precision in the most general adaptive quantum metrological scenarios. The bounds are proven to be asymptotically saturable and equivalent to the known parallel scheme bounds in the limit of large number of channel uses. This completely solves a long standing conjecture in the field of quantum metrology on asymptotic equivalence between parallel and adaptive strategies. The new bounds also allow to easily assess the potential benefits of invoking the non-standard causal superposition strategies, for which we prove, similarly to the adaptive case, the lack of asymptotic advantage over the parallel ones.

quant-ph↗

arXiv2022

Back to sources -- the role of losses and coherence in super-resolution imaging revisited

Photon losses are intrinsic for any translationally invariant optical imaging system with a non-trivial Point Spread Function, and the relation between the transmission factor and the coherence properties of an imaged object is universal -- we demonstrate the rigorous proof of this statement, based on the principles of quantum mechanics. The fundamental limit on the precision of estimating separation between two partially coherent sources is then derived. The careful study of the role of photon losses allows to resolve conflicting claims present in previous works. We compute the Quantum Fisher Information for the generic model of optical 4f imaging system, and use prior considerations to validate the result for a general, translationally invariant imaging apparatus. We prove that the spatial-mode demultiplexing (SPADE) measurement, optimal for non-coherent sources, remains optimal for an arbitrary degree of coherence. Moreover, we show that some approximations, omnipresent in theoretical works about optical imaging, inevitably lead to unphysical, zero-transmission models, resulting in misleading claims regarding fundamental resolution limits.

quant-ph↗

arXiv2021

Super-resolution Optical Fluctuation Imaging -- fundamental estimation theory perspective

We provide a quantitative analysis of super-resolution imaging techniques which exploit temporal fluctuations of luminosity of the sources in order to beat the Rayleigh limit. We define an operationally justified resolution gain figure of merit, that allows us to connect the estimation theory concepts with the ones typically used in the imaging community, and derive fundamental resolution limits that scale at most as the fourth-root of the mean luminosity of the sources. We fine-tune and benchmark the performance of state-of-the-art methods, focusing on the cumulant-based image processing techniques (known under the common acronym SOFI), taking into account the impact of limited photon number and sampling time.

quant-ph↗